Gear or rack-shaped tool for precision machining of tooth flanks particularly of hardened gears

In a gear or rack-shaped precision finishing tool for precision finishing of tooth flanks, particularly of hardened gears, including a tooth base member of metal having a coating which includes grains of a hard material such as cubic boron nitride (CBN) or diamond covering each tooth flank of said base member, the improvement comprising wherein said base member of said tool includes two halves on which each second tooth is removed to thereby provide sufficient space for the even application of said coating on the circumferentially facing sides of each of said tooth flanks of the remaining teeth, the remaining teeth each having a pair of oppositely circumferentially facing involute tooth flanks separated at the radial extremity by a land surface, said tooth flanks and land surface extending axially beyond said one side of said base member a distance which is approximately half of their length, said base members being oppositely directed and connected to each other so as to be fixed against relative rotation, wherein said axially projecting teeth of each half are disposed between the teeth of the other half, and wherein connecting means are provided for connecting said two halves together.